forked from git/git
/
builtin-merge.c
1225 lines (1085 loc) · 31.5 KB
/
builtin-merge.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Builtin "git merge"
*
* Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
*
* Based on git-merge.sh by Junio C Hamano.
*/
#include "cache.h"
#include "parse-options.h"
#include "builtin.h"
#include "run-command.h"
#include "diff.h"
#include "refs.h"
#include "commit.h"
#include "diffcore.h"
#include "revision.h"
#include "unpack-trees.h"
#include "cache-tree.h"
#include "dir.h"
#include "utf8.h"
#include "log-tree.h"
#include "color.h"
#include "rerere.h"
#include "help.h"
#include "merge-recursive.h"
#define DEFAULT_TWOHEAD (1<<0)
#define DEFAULT_OCTOPUS (1<<1)
#define NO_FAST_FORWARD (1<<2)
#define NO_TRIVIAL (1<<3)
struct strategy {
const char *name;
unsigned attr;
};
static const char * const builtin_merge_usage[] = {
"git merge [options] <remote>...",
"git merge [options] <msg> HEAD <remote>",
NULL
};
static int show_diffstat = 1, option_log, squash;
static int option_commit = 1, allow_fast_forward = 1;
static int allow_trivial = 1, have_message;
static struct strbuf merge_msg;
static struct commit_list *remoteheads;
static unsigned char head[20], stash[20];
static struct strategy **use_strategies;
static size_t use_strategies_nr, use_strategies_alloc;
static const char *branch;
static int verbosity;
static struct strategy all_strategy[] = {
{ "recursive", DEFAULT_TWOHEAD | NO_TRIVIAL },
{ "octopus", DEFAULT_OCTOPUS },
{ "resolve", 0 },
{ "ours", NO_FAST_FORWARD | NO_TRIVIAL },
{ "subtree", NO_FAST_FORWARD | NO_TRIVIAL },
};
static const char *pull_twohead, *pull_octopus;
static int option_parse_message(const struct option *opt,
const char *arg, int unset)
{
struct strbuf *buf = opt->value;
if (unset)
strbuf_setlen(buf, 0);
else if (arg) {
strbuf_addf(buf, "%s\n\n", arg);
have_message = 1;
} else
return error("switch `m' requires a value");
return 0;
}
static struct strategy *get_strategy(const char *name)
{
int i;
struct strategy *ret;
static struct cmdnames main_cmds, other_cmds;
static int loaded;
if (!name)
return NULL;
for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
if (!strcmp(name, all_strategy[i].name))
return &all_strategy[i];
if (!loaded) {
struct cmdnames not_strategies;
loaded = 1;
memset(¬_strategies, 0, sizeof(struct cmdnames));
load_command_list("git-merge-", &main_cmds, &other_cmds);
for (i = 0; i < main_cmds.cnt; i++) {
int j, found = 0;
struct cmdname *ent = main_cmds.names[i];
for (j = 0; j < ARRAY_SIZE(all_strategy); j++)
if (!strncmp(ent->name, all_strategy[j].name, ent->len)
&& !all_strategy[j].name[ent->len])
found = 1;
if (!found)
add_cmdname(¬_strategies, ent->name, ent->len);
exclude_cmds(&main_cmds, ¬_strategies);
}
}
if (!is_in_cmdlist(&main_cmds, name) && !is_in_cmdlist(&other_cmds, name)) {
fprintf(stderr, "Could not find merge strategy '%s'.\n", name);
fprintf(stderr, "Available strategies are:");
for (i = 0; i < main_cmds.cnt; i++)
fprintf(stderr, " %s", main_cmds.names[i]->name);
fprintf(stderr, ".\n");
if (other_cmds.cnt) {
fprintf(stderr, "Available custom strategies are:");
for (i = 0; i < other_cmds.cnt; i++)
fprintf(stderr, " %s", other_cmds.names[i]->name);
fprintf(stderr, ".\n");
}
exit(1);
}
ret = xcalloc(1, sizeof(struct strategy));
ret->name = xstrdup(name);
return ret;
}
static void append_strategy(struct strategy *s)
{
ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
use_strategies[use_strategies_nr++] = s;
}
static int option_parse_strategy(const struct option *opt,
const char *name, int unset)
{
if (unset)
return 0;
append_strategy(get_strategy(name));
return 0;
}
static int option_parse_n(const struct option *opt,
const char *arg, int unset)
{
show_diffstat = unset;
return 0;
}
static struct option builtin_merge_options[] = {
{ OPTION_CALLBACK, 'n', NULL, NULL, NULL,
"do not show a diffstat at the end of the merge",
PARSE_OPT_NOARG, option_parse_n },
OPT_BOOLEAN(0, "stat", &show_diffstat,
"show a diffstat at the end of the merge"),
OPT_BOOLEAN(0, "summary", &show_diffstat, "(synonym to --stat)"),
OPT_BOOLEAN(0, "log", &option_log,
"add list of one-line log to merge commit message"),
OPT_BOOLEAN(0, "squash", &squash,
"create a single commit instead of doing a merge"),
OPT_BOOLEAN(0, "commit", &option_commit,
"perform a commit if the merge succeeds (default)"),
OPT_BOOLEAN(0, "ff", &allow_fast_forward,
"allow fast forward (default)"),
OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
"merge strategy to use", option_parse_strategy),
OPT_CALLBACK('m', "message", &merge_msg, "message",
"message to be used for the merge commit (if any)",
option_parse_message),
OPT__VERBOSITY(&verbosity),
OPT_END()
};
/* Cleans up metadata that is uninteresting after a succeeded merge. */
static void drop_save(void)
{
unlink(git_path("MERGE_HEAD"));
unlink(git_path("MERGE_MSG"));
unlink(git_path("MERGE_MODE"));
}
static void save_state(void)
{
int len;
struct child_process cp;
struct strbuf buffer = STRBUF_INIT;
const char *argv[] = {"stash", "create", NULL};
memset(&cp, 0, sizeof(cp));
cp.argv = argv;
cp.out = -1;
cp.git_cmd = 1;
if (start_command(&cp))
die("could not run stash.");
len = strbuf_read(&buffer, cp.out, 1024);
close(cp.out);
if (finish_command(&cp) || len < 0)
die("stash failed");
else if (!len)
return;
strbuf_setlen(&buffer, buffer.len-1);
if (get_sha1(buffer.buf, stash))
die("not a valid object: %s", buffer.buf);
}
static void reset_hard(unsigned const char *sha1, int verbose)
{
int i = 0;
const char *args[6];
args[i++] = "read-tree";
if (verbose)
args[i++] = "-v";
args[i++] = "--reset";
args[i++] = "-u";
args[i++] = sha1_to_hex(sha1);
args[i] = NULL;
if (run_command_v_opt(args, RUN_GIT_CMD))
die("read-tree failed");
}
static void restore_state(void)
{
struct strbuf sb = STRBUF_INIT;
const char *args[] = { "stash", "apply", NULL, NULL };
if (is_null_sha1(stash))
return;
reset_hard(head, 1);
args[2] = sha1_to_hex(stash);
/*
* It is OK to ignore error here, for example when there was
* nothing to restore.
*/
run_command_v_opt(args, RUN_GIT_CMD);
strbuf_release(&sb);
refresh_cache(REFRESH_QUIET);
}
/* This is called when no merge was necessary. */
static void finish_up_to_date(const char *msg)
{
if (verbosity >= 0)
printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
drop_save();
}
static void squash_message(void)
{
struct rev_info rev;
struct commit *commit;
struct strbuf out = STRBUF_INIT;
struct commit_list *j;
int fd;
printf("Squash commit -- not updating HEAD\n");
fd = open(git_path("SQUASH_MSG"), O_WRONLY | O_CREAT, 0666);
if (fd < 0)
die_errno("Could not write to '%s'", git_path("SQUASH_MSG"));
init_revisions(&rev, NULL);
rev.ignore_merges = 1;
rev.commit_format = CMIT_FMT_MEDIUM;
commit = lookup_commit(head);
commit->object.flags |= UNINTERESTING;
add_pending_object(&rev, &commit->object, NULL);
for (j = remoteheads; j; j = j->next)
add_pending_object(&rev, &j->item->object, NULL);
setup_revisions(0, NULL, &rev, NULL);
if (prepare_revision_walk(&rev))
die("revision walk setup failed");
strbuf_addstr(&out, "Squashed commit of the following:\n");
while ((commit = get_revision(&rev)) != NULL) {
strbuf_addch(&out, '\n');
strbuf_addf(&out, "commit %s\n",
sha1_to_hex(commit->object.sha1));
pretty_print_commit(rev.commit_format, commit, &out, rev.abbrev,
NULL, NULL, rev.date_mode, 0);
}
if (write(fd, out.buf, out.len) < 0)
die_errno("Writing SQUASH_MSG");
if (close(fd))
die_errno("Finishing SQUASH_MSG");
strbuf_release(&out);
}
static void finish(const unsigned char *new_head, const char *msg)
{
struct strbuf reflog_message = STRBUF_INIT;
if (!msg)
strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
else {
if (verbosity >= 0)
printf("%s\n", msg);
strbuf_addf(&reflog_message, "%s: %s",
getenv("GIT_REFLOG_ACTION"), msg);
}
if (squash) {
squash_message();
} else {
if (verbosity >= 0 && !merge_msg.len)
printf("No merge message -- not updating HEAD\n");
else {
const char *argv_gc_auto[] = { "gc", "--auto", NULL };
update_ref(reflog_message.buf, "HEAD",
new_head, head, 0,
DIE_ON_ERR);
/*
* We ignore errors in 'gc --auto', since the
* user should see them.
*/
run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
}
}
if (new_head && show_diffstat) {
struct diff_options opts;
diff_setup(&opts);
opts.output_format |=
DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
opts.detect_rename = DIFF_DETECT_RENAME;
if (diff_use_color_default > 0)
DIFF_OPT_SET(&opts, COLOR_DIFF);
if (diff_setup_done(&opts) < 0)
die("diff_setup_done failed");
diff_tree_sha1(head, new_head, "", &opts);
diffcore_std(&opts);
diff_flush(&opts);
}
/* Run a post-merge hook */
run_hook(NULL, "post-merge", squash ? "1" : "0", NULL);
strbuf_release(&reflog_message);
}
/* Get the name for the merge commit's message. */
static void merge_name(const char *remote, struct strbuf *msg)
{
struct object *remote_head;
unsigned char branch_head[20], buf_sha[20];
struct strbuf buf = STRBUF_INIT;
struct strbuf bname = STRBUF_INIT;
const char *ptr;
int len, early;
strbuf_branchname(&bname, remote);
remote = bname.buf;
memset(branch_head, 0, sizeof(branch_head));
remote_head = peel_to_type(remote, 0, NULL, OBJ_COMMIT);
if (!remote_head)
die("'%s' does not point to a commit", remote);
strbuf_addstr(&buf, "refs/heads/");
strbuf_addstr(&buf, remote);
resolve_ref(buf.buf, branch_head, 0, NULL);
if (!hashcmp(remote_head->sha1, branch_head)) {
strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
sha1_to_hex(branch_head), remote);
goto cleanup;
}
/* See if remote matches <name>^^^.. or <name>~<number> */
for (len = 0, ptr = remote + strlen(remote);
remote < ptr && ptr[-1] == '^';
ptr--)
len++;
if (len)
early = 1;
else {
early = 0;
ptr = strrchr(remote, '~');
if (ptr) {
int seen_nonzero = 0;
len++; /* count ~ */
while (*++ptr && isdigit(*ptr)) {
seen_nonzero |= (*ptr != '0');
len++;
}
if (*ptr)
len = 0; /* not ...~<number> */
else if (seen_nonzero)
early = 1;
else if (len == 1)
early = 1; /* "name~" is "name~1"! */
}
}
if (len) {
struct strbuf truname = STRBUF_INIT;
strbuf_addstr(&truname, "refs/heads/");
strbuf_addstr(&truname, remote);
strbuf_setlen(&truname, truname.len - len);
if (resolve_ref(truname.buf, buf_sha, 0, NULL)) {
strbuf_addf(msg,
"%s\t\tbranch '%s'%s of .\n",
sha1_to_hex(remote_head->sha1),
truname.buf + 11,
(early ? " (early part)" : ""));
strbuf_release(&truname);
goto cleanup;
}
}
if (!strcmp(remote, "FETCH_HEAD") &&
!access(git_path("FETCH_HEAD"), R_OK)) {
FILE *fp;
struct strbuf line = STRBUF_INIT;
char *ptr;
fp = fopen(git_path("FETCH_HEAD"), "r");
if (!fp)
die_errno("could not open '%s' for reading",
git_path("FETCH_HEAD"));
strbuf_getline(&line, fp, '\n');
fclose(fp);
ptr = strstr(line.buf, "\tnot-for-merge\t");
if (ptr)
strbuf_remove(&line, ptr-line.buf+1, 13);
strbuf_addbuf(msg, &line);
strbuf_release(&line);
goto cleanup;
}
strbuf_addf(msg, "%s\t\tcommit '%s'\n",
sha1_to_hex(remote_head->sha1), remote);
cleanup:
strbuf_release(&buf);
strbuf_release(&bname);
}
static int git_merge_config(const char *k, const char *v, void *cb)
{
if (branch && !prefixcmp(k, "branch.") &&
!prefixcmp(k + 7, branch) &&
!strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
const char **argv;
int argc;
char *buf;
buf = xstrdup(v);
argc = split_cmdline(buf, &argv);
if (argc < 0)
die("Bad branch.%s.mergeoptions string", branch);
argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
argc++;
parse_options(argc, argv, NULL, builtin_merge_options,
builtin_merge_usage, 0);
free(buf);
}
if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
show_diffstat = git_config_bool(k, v);
else if (!strcmp(k, "pull.twohead"))
return git_config_string(&pull_twohead, k, v);
else if (!strcmp(k, "pull.octopus"))
return git_config_string(&pull_octopus, k, v);
else if (!strcmp(k, "merge.log") || !strcmp(k, "merge.summary"))
option_log = git_config_bool(k, v);
return git_diff_ui_config(k, v, cb);
}
static int read_tree_trivial(unsigned char *common, unsigned char *head,
unsigned char *one)
{
int i, nr_trees = 0;
struct tree *trees[MAX_UNPACK_TREES];
struct tree_desc t[MAX_UNPACK_TREES];
struct unpack_trees_options opts;
memset(&opts, 0, sizeof(opts));
opts.head_idx = 2;
opts.src_index = &the_index;
opts.dst_index = &the_index;
opts.update = 1;
opts.verbose_update = 1;
opts.trivial_merges_only = 1;
opts.merge = 1;
trees[nr_trees] = parse_tree_indirect(common);
if (!trees[nr_trees++])
return -1;
trees[nr_trees] = parse_tree_indirect(head);
if (!trees[nr_trees++])
return -1;
trees[nr_trees] = parse_tree_indirect(one);
if (!trees[nr_trees++])
return -1;
opts.fn = threeway_merge;
cache_tree_free(&active_cache_tree);
for (i = 0; i < nr_trees; i++) {
parse_tree(trees[i]);
init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
}
if (unpack_trees(nr_trees, t, &opts))
return -1;
return 0;
}
static void write_tree_trivial(unsigned char *sha1)
{
if (write_cache_as_tree(sha1, 0, NULL))
die("git write-tree failed to write a tree");
}
static int try_merge_strategy(const char *strategy, struct commit_list *common,
const char *head_arg)
{
const char **args;
int i = 0, ret;
struct commit_list *j;
struct strbuf buf = STRBUF_INIT;
int index_fd;
struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
index_fd = hold_locked_index(lock, 1);
refresh_cache(REFRESH_QUIET);
if (active_cache_changed &&
(write_cache(index_fd, active_cache, active_nr) ||
commit_locked_index(lock)))
return error("Unable to write index.");
rollback_lock_file(lock);
if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
int clean;
struct commit *result;
struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
int index_fd;
struct commit_list *reversed = NULL;
struct merge_options o;
if (remoteheads->next) {
error("Not handling anything other than two heads merge.");
return 2;
}
init_merge_options(&o);
if (!strcmp(strategy, "subtree"))
o.subtree_merge = 1;
o.branch1 = head_arg;
o.branch2 = remoteheads->item->util;
for (j = common; j; j = j->next)
commit_list_insert(j->item, &reversed);
index_fd = hold_locked_index(lock, 1);
clean = merge_recursive(&o, lookup_commit(head),
remoteheads->item, reversed, &result);
if (active_cache_changed &&
(write_cache(index_fd, active_cache, active_nr) ||
commit_locked_index(lock)))
die ("unable to write %s", get_index_file());
rollback_lock_file(lock);
return clean ? 0 : 1;
} else {
args = xmalloc((4 + commit_list_count(common) +
commit_list_count(remoteheads)) * sizeof(char *));
strbuf_addf(&buf, "merge-%s", strategy);
args[i++] = buf.buf;
for (j = common; j; j = j->next)
args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
args[i++] = "--";
args[i++] = head_arg;
for (j = remoteheads; j; j = j->next)
args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
args[i] = NULL;
ret = run_command_v_opt(args, RUN_GIT_CMD);
strbuf_release(&buf);
i = 1;
for (j = common; j; j = j->next)
free((void *)args[i++]);
i += 2;
for (j = remoteheads; j; j = j->next)
free((void *)args[i++]);
free(args);
discard_cache();
if (read_cache() < 0)
die("failed to read the cache");
return -ret;
}
}
static void count_diff_files(struct diff_queue_struct *q,
struct diff_options *opt, void *data)
{
int *count = data;
(*count) += q->nr;
}
static int count_unmerged_entries(void)
{
const struct index_state *state = &the_index;
int i, ret = 0;
for (i = 0; i < state->cache_nr; i++)
if (ce_stage(state->cache[i]))
ret++;
return ret;
}
static int checkout_fast_forward(unsigned char *head, unsigned char *remote)
{
struct tree *trees[MAX_UNPACK_TREES];
struct unpack_trees_options opts;
struct tree_desc t[MAX_UNPACK_TREES];
int i, fd, nr_trees = 0;
struct dir_struct dir;
struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
refresh_cache(REFRESH_QUIET);
fd = hold_locked_index(lock_file, 1);
memset(&trees, 0, sizeof(trees));
memset(&opts, 0, sizeof(opts));
memset(&t, 0, sizeof(t));
memset(&dir, 0, sizeof(dir));
dir.flags |= DIR_SHOW_IGNORED;
dir.exclude_per_dir = ".gitignore";
opts.dir = &dir;
opts.head_idx = 1;
opts.src_index = &the_index;
opts.dst_index = &the_index;
opts.update = 1;
opts.verbose_update = 1;
opts.merge = 1;
opts.fn = twoway_merge;
trees[nr_trees] = parse_tree_indirect(head);
if (!trees[nr_trees++])
return -1;
trees[nr_trees] = parse_tree_indirect(remote);
if (!trees[nr_trees++])
return -1;
for (i = 0; i < nr_trees; i++) {
parse_tree(trees[i]);
init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
}
if (unpack_trees(nr_trees, t, &opts))
return -1;
if (write_cache(fd, active_cache, active_nr) ||
commit_locked_index(lock_file))
die("unable to write new index file");
return 0;
}
static void split_merge_strategies(const char *string, struct strategy **list,
int *nr, int *alloc)
{
char *p, *q, *buf;
if (!string)
return;
buf = xstrdup(string);
q = buf;
for (;;) {
p = strchr(q, ' ');
if (!p) {
ALLOC_GROW(*list, *nr + 1, *alloc);
(*list)[(*nr)++].name = xstrdup(q);
free(buf);
return;
} else {
*p = '\0';
ALLOC_GROW(*list, *nr + 1, *alloc);
(*list)[(*nr)++].name = xstrdup(q);
q = ++p;
}
}
}
static void add_strategies(const char *string, unsigned attr)
{
struct strategy *list = NULL;
int list_alloc = 0, list_nr = 0, i;
memset(&list, 0, sizeof(list));
split_merge_strategies(string, &list, &list_nr, &list_alloc);
if (list) {
for (i = 0; i < list_nr; i++)
append_strategy(get_strategy(list[i].name));
return;
}
for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
if (all_strategy[i].attr & attr)
append_strategy(&all_strategy[i]);
}
static int merge_trivial(void)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list *parent = xmalloc(sizeof(*parent));
write_tree_trivial(result_tree);
printf("Wonderful.\n");
parent->item = lookup_commit(head);
parent->next = xmalloc(sizeof(*parent->next));
parent->next->item = remoteheads->item;
parent->next->next = NULL;
commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
finish(result_commit, "In-index merge");
drop_save();
return 0;
}
static int finish_automerge(struct commit_list *common,
unsigned char *result_tree,
const char *wt_strategy)
{
struct commit_list *parents = NULL, *j;
struct strbuf buf = STRBUF_INIT;
unsigned char result_commit[20];
free_commit_list(common);
if (allow_fast_forward) {
parents = remoteheads;
commit_list_insert(lookup_commit(head), &parents);
parents = reduce_heads(parents);
} else {
struct commit_list **pptr = &parents;
pptr = &commit_list_insert(lookup_commit(head),
pptr)->next;
for (j = remoteheads; j; j = j->next)
pptr = &commit_list_insert(j->item, pptr)->next;
}
free_commit_list(remoteheads);
strbuf_addch(&merge_msg, '\n');
commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
strbuf_addf(&buf, "Merge made by %s.", wt_strategy);
finish(result_commit, buf.buf);
strbuf_release(&buf);
drop_save();
return 0;
}
static int suggest_conflicts(void)
{
FILE *fp;
int pos;
fp = fopen(git_path("MERGE_MSG"), "a");
if (!fp)
die_errno("Could not open '%s' for writing",
git_path("MERGE_MSG"));
fprintf(fp, "\nConflicts:\n");
for (pos = 0; pos < active_nr; pos++) {
struct cache_entry *ce = active_cache[pos];
if (ce_stage(ce)) {
fprintf(fp, "\t%s\n", ce->name);
while (pos + 1 < active_nr &&
!strcmp(ce->name,
active_cache[pos + 1]->name))
pos++;
}
}
fclose(fp);
rerere();
printf("Automatic merge failed; "
"fix conflicts and then commit the result.\n");
return 1;
}
static struct commit *is_old_style_invocation(int argc, const char **argv)
{
struct commit *second_token = NULL;
if (argc > 1) {
unsigned char second_sha1[20];
if (get_sha1(argv[1], second_sha1))
return NULL;
second_token = lookup_commit_reference_gently(second_sha1, 0);
if (!second_token)
die("'%s' is not a commit", argv[1]);
if (hashcmp(second_token->object.sha1, head))
return NULL;
}
return second_token;
}
static int evaluate_result(void)
{
int cnt = 0;
struct rev_info rev;
/* Check how many files differ. */
init_revisions(&rev, "");
setup_revisions(0, NULL, &rev, NULL);
rev.diffopt.output_format |=
DIFF_FORMAT_CALLBACK;
rev.diffopt.format_callback = count_diff_files;
rev.diffopt.format_callback_data = &cnt;
run_diff_files(&rev, 0);
/*
* Check how many unmerged entries are
* there.
*/
cnt += count_unmerged_entries();
return cnt;
}
int cmd_merge(int argc, const char **argv, const char *prefix)
{
unsigned char result_tree[20];
struct strbuf buf = STRBUF_INIT;
const char *head_arg;
int flag, head_invalid = 0, i;
int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
struct commit_list *common = NULL;
const char *best_strategy = NULL, *wt_strategy = NULL;
struct commit_list **remotes = &remoteheads;
setup_work_tree();
if (file_exists(git_path("MERGE_HEAD")))
die("You have not concluded your merge. (MERGE_HEAD exists)");
if (read_cache_unmerged())
die("You are in the middle of a conflicted merge."
" (index unmerged)");
/*
* Check if we are _not_ on a detached HEAD, i.e. if there is a
* current branch.
*/
branch = resolve_ref("HEAD", head, 0, &flag);
if (branch && !prefixcmp(branch, "refs/heads/"))
branch += 11;
if (is_null_sha1(head))
head_invalid = 1;
git_config(git_merge_config, NULL);
/* for color.ui */
if (diff_use_color_default == -1)
diff_use_color_default = git_use_color_default;
argc = parse_options(argc, argv, prefix, builtin_merge_options,
builtin_merge_usage, 0);
if (verbosity < 0)
show_diffstat = 0;
if (squash) {
if (!allow_fast_forward)
die("You cannot combine --squash with --no-ff.");
option_commit = 0;
}
if (!argc)
usage_with_options(builtin_merge_usage,
builtin_merge_options);
/*
* This could be traditional "merge <msg> HEAD <commit>..." and
* the way we can tell it is to see if the second token is HEAD,
* but some people might have misused the interface and used a
* committish that is the same as HEAD there instead.
* Traditional format never would have "-m" so it is an
* additional safety measure to check for it.
*/
if (!have_message && is_old_style_invocation(argc, argv)) {
strbuf_addstr(&merge_msg, argv[0]);
head_arg = argv[1];
argv += 2;
argc -= 2;
} else if (head_invalid) {
struct object *remote_head;
/*
* If the merged head is a valid one there is no reason
* to forbid "git merge" into a branch yet to be born.
* We do the same for "git pull".
*/
if (argc != 1)
die("Can merge only exactly one commit into "
"empty head");
if (squash)
die("Squash commit into empty head not supported yet");
if (!allow_fast_forward)
die("Non-fast-forward commit does not make sense into "
"an empty head");
remote_head = peel_to_type(argv[0], 0, NULL, OBJ_COMMIT);
if (!remote_head)
die("%s - not something we can merge", argv[0]);
update_ref("initial pull", "HEAD", remote_head->sha1, NULL, 0,
DIE_ON_ERR);
reset_hard(remote_head->sha1, 0);
return 0;
} else {
struct strbuf msg = STRBUF_INIT;
/* We are invoked directly as the first-class UI. */
head_arg = "HEAD";
/*
* All the rest are the commits being merged;
* prepare the standard merge summary message to
* be appended to the given message. If remote
* is invalid we will die later in the common
* codepath so we discard the error in this
* loop.
*/
for (i = 0; i < argc; i++)
merge_name(argv[i], &msg);
fmt_merge_msg(option_log, &msg, &merge_msg);
if (merge_msg.len)
strbuf_setlen(&merge_msg, merge_msg.len-1);
}
if (head_invalid || !argc)
usage_with_options(builtin_merge_usage,
builtin_merge_options);
strbuf_addstr(&buf, "merge");
for (i = 0; i < argc; i++)
strbuf_addf(&buf, " %s", argv[i]);
setenv("GIT_REFLOG_ACTION", buf.buf, 0);
strbuf_reset(&buf);
for (i = 0; i < argc; i++) {
struct object *o;
struct commit *commit;
o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
if (!o)
die("%s - not something we can merge", argv[i]);
commit = lookup_commit(o->sha1);
commit->util = (void *)argv[i];
remotes = &commit_list_insert(commit, remotes)->next;
strbuf_addf(&buf, "GITHEAD_%s", sha1_to_hex(o->sha1));
setenv(buf.buf, argv[i], 1);
strbuf_reset(&buf);
}
if (!use_strategies) {
if (!remoteheads->next)
add_strategies(pull_twohead, DEFAULT_TWOHEAD);
else
add_strategies(pull_octopus, DEFAULT_OCTOPUS);
}
for (i = 0; i < use_strategies_nr; i++) {
if (use_strategies[i]->attr & NO_FAST_FORWARD)
allow_fast_forward = 0;
if (use_strategies[i]->attr & NO_TRIVIAL)
allow_trivial = 0;
}
if (!remoteheads->next)
common = get_merge_bases(lookup_commit(head),
remoteheads->item, 1);
else {
struct commit_list *list = remoteheads;
commit_list_insert(lookup_commit(head), &list);
common = get_octopus_merge_bases(list);
free(list);
}
update_ref("updating ORIG_HEAD", "ORIG_HEAD", head, NULL, 0,
DIE_ON_ERR);
if (!common)
; /* No common ancestors found. We need a real merge. */
else if (!remoteheads->next && !common->next &&
common->item == remoteheads->item) {
/*
* If head can reach all the merge then we are up to date.
* but first the most common case of merging one remote.
*/
finish_up_to_date("Already up-to-date.");
return 0;
} else if (allow_fast_forward && !remoteheads->next &&
!common->next &&
!hashcmp(common->item->object.sha1, head)) {
/* Again the most common case of merging one remote. */